Academictask provides MCQs of Physics from Basic to Advance, so that you can prepare accordingly. Physics Mcqs section is useful for both students and job seekers i.e MCAT ECAT ETEA test preparation, PPSC Test, FPSC Test
81. The periodic alternation of sound between maximum and minimum loudness are called___________________?
A. silence zone
B. interference
C. beats
D. resonance
82. Beats are the results of____________________?
A. diffraction of sound waves
B. constructive and destructive interference
C. polarization
D. destructive interference
83. Doppler effect applies to____________________?
A. sound wave only
B. light wave only
C. both sound and light waves
D. neither sound nor light wave
84. A simple pendulum has a bob of mass m and its frequency is f. If we replaced the bob with a heavier one say of 2m then that will be its new frequency ?
A. 1/4f
B. 1/2f
C. frequency lower than 20 Hz
D. 2f
85. In open organ pipe___________________?
A. only even harmonics are present
B. only odd harmonics are present
C. both even and odd harmonics are present
D. selected harmonics are present
86. Sound waves do not travel in vacuum because ___________________?
A. they are transverse waves
B. they are stationary waves
C. they require material medium for propagation
D. they do not have enough energy
87. Increase in velocity of sound in the air for 1°C rise in temperature is_________________?
A. 1.61 ms-1
B. 61.0 ms-1
C. 0.61 ms-1
D. 2.00 ms-1
88. On loading the prong of a tuning form with wax its frequency____________________?
A. increases
B. decreases
C. remains unchanged
D. may increase or decrease
89. The normal ear is the most sensitive in the frequency range___________________?
A. 20000 to 30000 hertz
B. 10 to 20 hertz
C. 2000 to 4000 hertz
D. 6000 to 8000 hertz
90. The velocity of sound in air would become double than its velocity at 0°C at temperature________________?
A. 313°C
B. 586°C
C. 819°C
D. 1172°C